Imaging systems can determine the orientation of an object by analysis of a number of successive images of the object through digital signal processing. When two objects are approaching each other (one or both objects may be moving) any deviation from the required direction needs to be quickly and accurately determined. Prior art methods do not presently provide an optimum performance in order to control a servo mechanism for re-orientation.
U.S. Pat. No. 4,724,480 discloses an arrangement for determining the alignment of one object relative to another object. A light pattern is projected from a first object onto a second object. The signals from a camera mounted on the first object are used to determine the relative position and orientation of the second object.
U.S. Pat. No. 5,475,584 discloses a method for recovering the orientation of a camera with respect to a coordinate system by projecting onto an image plane three images of three gratings formed on three planes with three wavelength vectors.
U.S. Pat. No. 5,982,549 discloses a vision system that increases the field of view of an electronic binocular system without degrading image quality. The imaging device comprises a compression lens and an image sensor. The viewing device comprises an image display and a decomposition lens. The decompression lens compensates for the effect of the compression lens so that the devices see the image as it was seen by the imaging device without any introduced distortion.
It would be desirable to provide an improved system and method for determining the orientation of an object which gave a strong indication of the error.